1. Field of the Invention
This invention relates to thickeners for increasing the viscosity of aqueous compositions. In particular, this invention relates to thickeners which are easily incorporated into aqueous-based cosmetics and latex paints.
2. Description of the Related Art
Many aqueous systems require thickeners in order to be useful for various types of applications. Such aqueous-based systems as cosmetics, protective coatings for paper and metal, printing inks, and latex paints all require the incorporation of thickeners in order to have the proper rheological characteristics for their particular uses. Many substances useful as thickeners are known in the art. These include natural polymers such as casein and alginates, and synthetic materials such as cellulose derivatives, acrylic polymers, and polyurethane polymers. Some thickeners for use in personal care products such as shampoos, facial cleaners, liquid hand soaps, and the like require prolonged mixing periods and high temperatures to be incorporated into the products to be thickened. In some instances, the effectiveness of some thickeners has been found to be influenced by the components in the compositions to be thickened. Thus, there is a need for thickeners for aqueous-based personal care products which are readily incorporated and whose efficacy is not affected by other components such as salts.